The switching power supply, sometimes referred to as the switching regulator, is a well known type of circuit that is used widely in the electronics industry. The switching power supply (“SPS”) is a power supply that provides the power supply function through low loss components such as capacitors, inductors and transformers, using switches. An advantage is that switches dissipate very little power, and thus power conversion can be accomplished with very little power loss. That is, they are high efficiency power sources.
A certain class of SPS circuit uses multiple phase clocks controlling respective multiple controllers, for example by way of a “master” controller controlling multiple “slave” controllers, with numerous advantages. One such advantage is that for circuits that demand a source of power having a high current and fast response time, slave SPS controllers may be placed in parallel with a phase shift of their control signals to cancel output current ripple, while providing a suitably fast response. An example of such an SPS controller is described in U.S. Pat. No. 6,819,577, which issued on Nov. 16, 2004, to Stefan Wlodzimierz Wiktor et al., which is commonly assigned, and which is hereby incorporated herein by reference.
The SPS controller described in the '577 patent is an excellent solution to prior art demands, and provides a relatively small and inexpensive multiple phase SPS circuit, while still maintaining high efficiency. However, further improvements are desirable.